Predictive Value of Auditory Perceptual Assessment of Voice in Diagnosis of Functional Voice Disorders and Minimal Associated Pathological Lesions

Abstract

Background: Auditory perceptual assessment is considered the preliminary assessment tool of disordered voice quality. The validity of perceptual measurement depends on characteristics of the raters and the stimuli. It is associated with minimal cost and no specialized instrumentation is required. Because auditory-perceptual evaluation of dysphonia has been heavily criticized on the basis of its reliability and validity, we conducted this study to assess the reliability of auditory perceptual assessment as one of the objective measures for assessment of voice disorders and to determine the predictive relationships between instrumental measures as endoscopic examination and perceptual ratings of impaired voice quality. Subjects and Methods:The study included 50 patients complaining of dysphonia with age ranges from 5 -61 years. Auditory perceptual assessment (APA) of patients' voices was done and voice recordings were assessed by three experienced phoniatricians in a double blind, randomized fashion. The examiners (Ex1.2.3) assessed the recorded voice quality by using the modified GRBAS scale. Laryngoscopic examination was performed using indirect laryngoscope, flexible fibrotic laryngoscopy as well as rigid laryngoscope. Results: Results showed considerable similarities among raters in assessing the disordered voice quality especially on assessing the overall grade of dysphonia and the "Strain" voice quality with strong inter-rater reliability (Cronbach's Alpha) was 0.780 and 0.710 respectively. However, data showed some differences with poor inter-rater reliability especially for ratings of glottal attack and associated laryngeal function as cough (Cronbach's Alpha) was 0.383 and 0.531 respectively. The study also showed significant relations on comparing between instrumental (video endoscopic) diagnosis and perceptual predictive diagnosis of patients' disordered voice quality according to two of the raters with P <0.03&0.04. Conclusion: This study showed considerable variability of the inter-rater reliability across parameters of disordered voice quality with high inter-rater reliability for some parameters and low for others. Yet, there was a strong association between instrumental diagnostic measures and the perceptual predictive diagnosis denoting a clear relationship between listener's judgments of disordered voice quality and the underlying vocal pathology; a thing that is in favor for the validity of APA as a popular and fundamental tool for the assessment of vocal impairment.